RU2822314C1 - Device for static torsion testing of elastic elements - Google Patents

Abstract

FIELD: testing.

SUBSTANCE: invention relates to testing equipment and can be used to determine the torsional load characteristic of elastic rope or composite elements. Device comprises side brackets (3, 4) attached to longitudinal plate (2), fixed and rotary attachment parts of tested elastic element (1), means of applied force, lever. Fixed and rotary parts are made in the form of universal grippers with replaceable inserts-crutches (13, 22). Outer diameters of all inserts (13, 22) are identical, and inner diameters are different, for specific diameters of the tested elastic element (1). Rotary gripper is attached to side bracket (3) and is equipped with rotary trunnion (16) with a bearing, a loading device and a graduation scale with a pointer. Fixed gripper is attached to longitudinal plate (2) with longitudinal slots (9) to ensure the possibility of testing elastic elements (1) of different length.

EFFECT: accurate determination of torsional stiffness and damping coefficient of elastic or composite elements.

1 cl, 7 dwg

Description

The invention relates to the field of testing equipment and is used in determining the load characteristics of elastic rope and composite elements in torsion for the purpose of designing and creating a wide range of modifications of rope and composite couplings.

A device for testing elastic couplings is known according to RF patent No. 2206880, “Device for testing elastic couplings” [1], which contains a coupling, a base, a movable and fixed rack with support legs, a centering device of a composite structure with many elements, a means of applied force made in the form of a composite fork mechanism containing two cheeks and a bracket.

The torque on the drive flange occurs through the eye and the cheek, and the second cheek rotates freely around the trunnion, thereby providing only torsional deformation of the elastic elements of the coupling [1].

A significant disadvantage of the known device is that it cannot be used to test the torsion of one piece of steel rope; it has a complex design, large mass and dimensions.

A device for testing elastic couplings is also known according to the RF utility model patent No. 199499, “Device for testing elastic couplings”, adopted as a prototype [2]

The device [2] contains a coupling under test with an elastic element made of steel rope, the drive and driven flanges of the coupling, a stationary stand with a support leg secured by means of fasteners to the base of the device, a centering device trunnion with a support base, fastening threaded holes of the driven stationary and drive movable flanges couplings, trunnion tenon, lever with root and nose - stepped parts with fastening means and eye, arrows with scale.

A significant drawback of the prototype [2] is also that the device cannot be used to test the torsion of one piece of steel rope and has a complex design.

The technical result of the proposed invention is to ensure accurate determination of the value of torsional stiffness and damping coefficient of elastic rods made of steel rope and composite materials of various shapes and sizes by using special universal grips and a prefabricated “U”-shaped housing.

The specified technical result is achieved by the fact that the design of the device for static testing is made only for one separate rope elastic element from ropes of different diameters made with a working part of both an arcuate shape with different radii and a rectilinear shape with different working lengths, for which the rotating and non-rotating parts of the device made in the form of universal grips with replaceable inserts-crackers, providing the possibility of step-by-step fastening and testing of ropes with specific diameters, while the rotary universal grip is equipped with a side bracket, a rotating pin with a bearing, a loading device with a graduated scale with an arrow, and a fixed universal grip is equipped with a longitudinal a bracket with longitudinal grooves for the possibility of testing elastic elements (rope sections) with different lengths by moving a fixed gripper along the grooves and then fixing the position of the gripper.

The essence of the invention is illustrated by drawings:

fig. 1 - general view of the device;

fig. 2 - side view of the device - from the side of the rotary grip;

fig. 3 - universal rotary grip body;

fig. 4 - cover of the universal rotary gripper

fig. 5 - universal fixed grip;

fig. 6, 7 - external views of the cracker inserts, in which the outer diameters are the same (for all sets in order to ensure the versatility of both movable and fixed grips), and the inner diameters are different, and are made for specific diameters of the elastic rope element.

The design of the device for static testing of rope elastic elements for torsion is presented in drawings, which indicate:

1 - Elastic rope element 1 tested for torsion (Fig. 1);

2 - Longitudinal plate (Fig. 1);

3, 4 - Side brackets;

5, 6 - Screw connections bracket 3, 4 to longitudinal plate 2 (Fig. 1, 2);

7 - Hole for attaching the side bracket 4 to the work table when testing the elastic element (Fig. 1);

8 - Hole for ease of unhindered installation of elastic rope element 1 (Fig. 1);

9 - Longitudinal grooves (Fig. 1), for the possibility of testing rope sections of different lengths by moving a universal fixed grip along them (Fig. 5) with subsequent fixation of the position;

10 - Fastening screws for fixing the position of the universal fixed grip (Fig. 1);

11 - Housing of the universal rotary gripper (Fig. 1, 3);

12 - Cover of the universal rotary gripper (Fig. 1, 4);

13, 22 - Replaceable inserts-crackers of universal rotary and fixed grippers (Fig. 1);

14, 15 - Longitudinal semicircular grooves of the body 11 (Fig. 1, 3) and cover 12 (Fig. 1, 4) of the universal rotary gripper for inserts-crackers 13 (Fig. 1, 6, 7);

16 - Rotary pin of the universal gripper (Fig. 1);

17 - Screw connection of the cover 12 to the body 11 of the universal rotary gripper (Fig. 1);

18 - Screw connection of the rotary axle 16 to the body 11 (Fig. 1, 3) of the universal rotary grip;

19 - bearing of the axle (Fig. 1);

20, 21 - Body and cover of the universal fixed gripper (Fig. 1, 5);

23 - screw connection of the cover 21 with the body 20 of the universal fixed grip (Fig. 1);

24, 25 - Longitudinal semicircular grooves of the body 20 (Fig. 5) and the cover 21 (Fig. 5) of the universal non-rotary gripper for liners-crackers 22 (Fig. 1, 6, 7);

26 - lever (Fig. 1, 2);

27 - rod (Fig. 2);

28 - weights (Fig. 2);

29 - plate with a graduated scale (Fig. 1, 2);

30 - arrow (Fig. 2);

31 - washer (Fig. 2);

32 - mounting bolt (Fig. 1, 2).

The device for static testing of elastic elements for torsion contains an elastic rope element 1 tested for torsion (Fig. 1), rotating and non-rotating parts, made in the form of universal rotary (Fig. 3, 4), non-rotating (Fig. 5) elastic fastening grips rope element 1, means of applied force (Fig. 2), longitudinal plate 2 and side brackets 3, 4 (Fig. 1).

The side brackets 3, 4 are fastened to the longitudinal plate 2 using screw connections 5, 6 (Fig. 1, 2).

The side bracket 3 (Fig. 1) serves to accommodate and secure the rotary grip (Fig. 3, 4) and the means of applied force (Fig. 1, 2).

The side bracket 4 (Fig. 1) is intended for attaching the device to the desktop (the desktop is not shown in the figures), for which a threaded hole 7 is provided. For convenience and smooth installation of the elastic element 1, the side bracket 3 is made with a hole 8 (Fig. . 1).

The longitudinal plate 2 (Fig. 1) is made of longitudinal grooves 9 (in Fig. 1, one of the grooves 9 is shown in section), to make it possible to test the rope elastic element 1 with different lengths by moving the fixed grip along the grooves 9 (in Fig. 1 , the directions of movement are shown by arrows) with subsequent fixation of the position (grip) with fastening screws 10. The grooves 9 can also serve to fasten the device to the desktop (the desktop is not shown in the presented figures).

The rotary universal gripper (Fig. 3, 4) contains a body 11 (Fig. 1, 3), a cover 12 (Fig. 1, 4), replaceable inserts with crackers 13, longitudinal semicircular grooves 14 (Fig. 1, 3), 15 (Fig. 4) under the cracker inserts, and the rotary axle 16 (Fig. 1).

The cover 12 of the rotary universal grip is secured to its body 11 by a screw connection 17 (Fig. 1).

The rotary axle 16 (Fig. 1) is attached to the body 11 (Fig. 1, 3) of the universal rotary gripper using a screw connection 18 (Fig. 1).

The rotary axle 16 (Fig. 1) is equipped with a bearing 19.

The universal fixed gripper (Fig. 5) is made of two parts, a body 20 (Fig. 1, 5) and a cover 21 with replaceable cracker inserts 22. The cracker inserts 22 (Fig. 1) of the fixed gripper are similar to the crackers 13 of the rotary gripper.

External views of the cracker inserts in two versions (for the options for using an elastic rope element with a smaller and larger rope diameter are presented in Fig. 6, 7. To ensure versatility, both movable (Fig. 1, 3, 4) and stationary (Fig. 1, 5 ) of the grips, the outer diameters of all the cracker inserts are made the same, and the inner diameters are different, for the specific diameters of the elastic rope element 1 (Fig. 1, 6, 7).

The cover 21 (Fig. 1, 5) of the universal fixed grip is secured to its body 20 by a screw connection 23 (Fig. 1).

The loading device contains a lever 26 (Fig. 1, 2), a rod 27 (Fig. 2), weights 28 (Fig. 2), a plate 29 (Fig. 1, 2) with a graduated scale (Fig. 2), an arrow 30 ( Fig. 2), washer 31 (Fig. 2), mounting bolt 32 (Fig. 1, 2).

The versatility of the device is ensured by the following features:

1. The same outer diameters of paired sets of replaceable cracker inserts 13, 22 (Fig. 1) and different inner diameters (Fig. 6, 7) for the elastic rope element 1.

2. Carrying out static tests of various versions of steel rope elastic elements 1 with different curvatures of the working part, by using longitudinal grooves 9 (Fig. 1) on the longitudinal plate 2 (Fig. 1).

The procedure for preparing and conducting static tests of the elastic rope element 1 (Fig. 1) is as follows.

1. Before testing the elastic rope element 1 (Fig. 1) with curvature, a test plan is drawn up, where the main initial parameter is the choice of the maximum angle of twist (rope elastic element 1), for example, 30°. The angle of twist is determined by arrow 30 and scale 29 (Fig. 2).

2. Install and secure the ends of the test sample of the elastic rope element 1 (Fig. 1) with the selected curvature and diameter of the rope, the inserts of the crackers 13, 22 in the corresponding universal components rotating (11, 12) and fixed (20, 21) grips (Fig. 1).

3. By preliminary training of the tested elastic rope element 1, the torque recording step is selected according to the angle of twist, for example, after 2° with the selection of the appropriate weight using weights 28 (Fig. 2).

4. Then begin applying torque to the elastic rope element 1 at an angular deformation rate ranging from 1 to 10 mm per minute, recording the value of the corresponding torque every 2°. When torque is applied using a loading device under the action of lever 26 (Fig. 1, 2) on the axle 16 (Fig. 1) of the rotary gripper, angular deformation of the middle-working part of the rope elastic element 1 occurs, since one end of the rope is fixed between the body 20 and the cover 21 of the fixed grip (Fig. 1). To stabilize the elastic-damping characteristics of testing the rope elastic element 1, at least three cycles should be performed.

5. After reaching the selected (for example, 30°) angle of twist of the rope elastic element 1 (Fig. 1), slow unloading begins with corresponding registration of the torque.

6. As a result, the static load characteristic of the rope elastic element 1 (Fig. 1) is obtained in the form of a hysteresis loop.

7. By processing the load characteristics, the values of compliance (or static rigidity) and damping coefficients are determined, which can be used as initial data when designing and creating a wide range of modifications of rope couplings.

Thus, the above distinctive design features of the proposed technical solution in comparison with the prototype [2] confirm the novelty and versatility of the device, which ensures the determination of torsional rigidity and damping coefficient of elastic rods of different curvatures from steel ropes of various diameters, including composite materials.

Claims (1)

A device for static testing of elastic elements for torsion, containing an elastic element being tested for torsion, a fixed and rotating part of the elastic element fastening, a means of applied force, a lever, characterized in that the rotating and non-rotating parts of the device are made in the form of universal grips with replaceable inserts-crackers for fixing only one elastic element with the possibility of its variability in terms of diameter and length, as well as in the design of its working part, both arc-shaped with different radii and rectilinear, while the rotary universal grip is attached to the side bracket and is equipped with a rotary axle with a bearing, a loading device, a graduated scale with an arrow, and a fixed universal grip is attached to a longitudinal plate with longitudinal grooves for testing elastic elements of different lengths.